Uhler's Water Bug, Giant Water Bug

No creature is deliberately "mean", or has no place in the order of things, other than humans.

These bugs usually keep to the water, occasionally emerging and flying around, attracted to lights as most bugs are. Nearly any bug with piercing, biting, and chewing mouthparts will bite if provoked.

They are a vital part in pond life as a predator, and should typically be left alone, unless they are intruding on a small water garden and eating fish, and you certainly wouldn't want to add one to an aquarium. Remember, dragonfly larvae also fill a similar role, hiding in plants and debris and eating smaller aquatic creatures, till they emerge as dragonflies and eat mosquitos and things.

it is mean and can give a painful bite. It is of no use in ecology that I can find. It eats small fish, frogs, and small birds. It feeds by piercing the animal with sharp point on its front legs. It injects a enzyme immediately paralyzing them. The enzyme dissovles and liquidifies all but the skin. Then it drinks the fluids.
It is considered a deliacacy(spelling) in Asia eaten raw or cooked
It is also call the Electric Bug as they will come to lights when they fly from pond to pond during breeding season when looking for a mate